"We are again seeing these maniacal attempts to exploit the Russian theme in the US election campaign," Russian presidential spokesman Dmitry Peskov told journalists on Tuesday. “This absurd news was immediately refuted by the family of a prominent presidential candidate.”

On Sunday, Clinton’s campaign manager, Robby Mook, claimed in an interview with CNN that “experts are telling us that Russian state actors broke into the DNC (Democratic National Committee), stole these emails, and other experts are now saying that the Russians are releasing these emails for the purpose of actually helping Donald Trump.”

When asked what kind of evidence he had to back up that theory, Mook answered: “Well, we need the experts to speak on this. It's been reported on in the press that the hackers that got into the DNC are very likely to be working in coordination with Russia.”

In mid-June, The Washington Post reported that lone hacker Guccifer 2.0 claimed credit for breaking into the DNC's network.

Nearly 20,000 emails and more than 8,000 attachments from the DNC were released by WikiLeaks on July 22, exposing details of Clinton’s presidential campaign. Many of the emails indicate that top DNC officials used their influence against Bernie Sanders.

Peskov also recalled other reports published in the pro-Democratic US media, which claimed that Trump's foreign policy adviser Carter Page, who visited Moscow in early July, allegedly had a meeting with the head of the Kremlin's administration, Sergey Ivanov.

“I asked Sergey Borisovich Ivanov, whether he had met that man (Carter Page). And Sergey Borisovich told me he makes no comment to the delirious news,” Peskov said, adding that the American presidential campaign continues to exploit the Russian card without bothering to invent anything new.

"This is not good for our bilateral relations, but we understand that we simply have to get through this unpleasant period," Peskov said.

In response to a reporter’s question on allegations that Russia was behind the DNC email leaks, Russian Foreign Minister Sergey Lavrov had a concise reply on Tuesday, stating: “I don't want to use four-letter words.”

Lavrov was speaking ahead of talks at the ASEAN summit in Laos. US Secretary of State John Kerry, who was present at the time, also seemed to feel uncomfortable with the reporter's question.

In a Skype interview with NBC published on Monday, WikiLeaks founder Julian Assange said “there is no proof whatsoever” that the leaked emails came from Russia. He refused, however, to relay the source of the emails.

Assange said the focus should be on the content of the documents concerning Hillary Clinton, Bernie Sanders, and the Democratic Party.

“The real story is what these emails contain, and they show collusion at the very top of the Democratic Party” to obstruct Sanders’ campaign, Assange argued.

“Would Hillary Clinton have won anyway?” Assange asked. “Maybe, maybe not. I think that it’s completely up in the air now, and so the result of the nomination process has no political legitimacy.”